Determining the spotted kernel damage of true bugs (Hemiptera: Pentatomidae, Coreidae and Acanthosomatidae) on different hazelnut (Corylus avellana L.) cultivars

Abstract

Some species of Pentatomidae, Coreidae and Acanthosomatidae families of Hemiptera cause over 10% damaged hazelnut kernels, and this rate differs according to regions in Turkey. This situation leads to complaints in exportation. In addition to this damage, these pests may cause prematurely dropped nuts that have light brown in color and shriveled at the bottom, well developed nuts in size and grayish-black in color without kernel, undeveloped nuts with shriveled kernels. The most important pest causing spotted kernel damage in hazelnut orchards in terms of both intensity and extensity is Palomena prasina. In this study, the damage ratios of Palomena prasina as well as other sucking insects in commonly produced hazelnut types (Cakildak, Fosa, Karafindik, Mincane, Palaz, Sivri and Tombul) were determined. The study was conducted in hazelnut orchards located in Duzce, Giresun, Ordu, Sakarya, Samsun and Trabzon provinces in 2010-2011. In these provinces, samples were taken from 76 orchards belonging to 19 districts in 2010 and 17 districts in 2011, and a total of 41614 fruits were examined. Spotted kernel damage, as the first aim of the study, and other damages of these pests were determined. The highest spotted kernel ratio was found in Fosa (9.27%) cultivar followed by Sivri (8.38%), Mincane (7.64%), Tombul (5.82%), Palaz (5.26%), Karafindik (5.24%) and Cakildak (5.01%) in 2010. In 2011, the highest spotted kernel ratio was in Fosa (11.68%), Mincane (8.24%), Tombul (6.67%), Cakildak (6.49%), Sivri (5.60%), Palaz (5.56%) and Karafindik (5.20%). According to analysis, the differences among the spotted kernel ratios of hazelnut cultivars were found to be statistically insignificant (P>0.05; P=0.907).